Transpile ES6 even without node, just using rubyracer

config/application.rb

@@ -32,6 +32,7 @@ class Application < Rails::Application
     # -- all .rb files in that directory are automatically loaded.
 
     require 'discourse'
+    require 'es6_module_transpiler/rails'
     require 'js_locale_helper'
 
     # mocha hates us, active_support/testing/mochaing.rb line 2 is requiring the wrong

lib/es6_module_transpiler/rails.rb

@@ -0,0 +1,39 @@
+require 'es6_module_transpiler/rails/version'
+require 'es6_module_transpiler/tilt'
+require 'es6_module_transpiler/sprockets'
+
+module ES6ModuleTranspiler
+  def self.compile_to
+    @compile_to || :amd
+  end
+
+  def self.compile_to=(target)
+    @compile_to = target
+  end
+
+  def self.prefix_patterns
+    @prefix_patterns ||= []
+  end
+
+  def self.add_prefix_pattern(pattern, prefix)
+    prefix_patterns << [pattern, prefix]
+  end
+
+  def self.lookup_prefix(path)
+    _, prefix = prefix_patterns.detect {|pattern, prefix| pattern =~ path }
+
+    prefix
+  end
+
+  def self.transform=(transform)
+    @transform = transform
+  end
+
+  def self.transform
+    @transform
+  end
+
+  def self.compiler_options
+    @compiler_options ||= {}
+  end
+end

lib/es6_module_transpiler/rails/version.rb

@@ -0,0 +1,5 @@
+module ES6ModuleTranspiler
+  module Rails
+    VERSION = '0.4.0'
+  end
+end

lib/es6_module_transpiler/sprockets.rb

@@ -0,0 +1,3 @@
+require 'sprockets'
+
+Sprockets.register_engine '.es6', Tilt::ES6ModuleTranspilerTemplate